test: Run steami_screen on GC9A01 real device

[Charly-sketch]

Description
Test the steami_screen module with the GC9A01 display on real hardware.
The files have been implemented and integrated, but they have not yet been tested on physical hardware.

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Source
lib/steami_screen/

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Tasks

• Verify that GC9A01 display initialization works correctly
• Test basic rendering (clear, draw pixel, fill, etc.)
• Validate color rendering (especially rgb565)
• Test each widget individually on hardware
• Check performance (refresh rate, smoothness)
• Identify and fix any SPI / timing-related issues
• Document any limitations or unexpected behavior
• Update documentation if needed

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Widget inventory (all must work on hardware)
title, value, subtitle, bar, gauge, graph, menu, compass, watch, face

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Parent
feat: Migrate steami_screen library from tutorials repo. #266 — Migration umbrella issue

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Blocked by
Access to a working GC9A01 display for hardware testing